Phylum Nemertea (Rhynchocoela)

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Cerebral organs of nemerteans Most nemerteans possess a pair of complex cerebral organs with a ciliated epidermal invagination (cerebral canal) Canal ends are surrounded by nervous tissue of the cerebral ganglion and glandular tissue and also associated with lacunar blood spaces. Cilia move water along and aid in prey detection Overall the complete function of the cerebral organs is not completely known. Some pelagic hoplonemerteans and symbiotic genera (e.g. Carcinonemertes and Malacobdella do not have cerebral organs)
Reproduction Most nemerteans are dioecious. Protandry and simultaneous hermaphroditism is known System not as complex as flatworms. Numerous paired gonads (mesenchymal tissue) located in pouches in the body wall between successive intestinal diverticuli. During reproduction, a temporary gonoduct and gonopore develop for each gonad. Gametes are shed to the sea through gonopores and body wall ruptures. Chemotaxis plays a role in locating mates External fertilization. Synchronous spawning with neighboring nemerteans? Several nemerteans may form a mucous covered mass during spawning Asexual reproduction by regeneration. Not all species can regenerate in the same extreme fashion as Lineus
Page 1 and 2: Phylum Nemertea (Rhynchocoela) Gree
Page 3: Nemertean Bauplan “Functionally
Page 6 and 7: Feeding and digestion Proboscis is
Page 8 and 9: Comparison of Proboscis Types Credi
Page 10 and 11: Circulation and Gas Exchange Nemert
Page 12 and 13: Excretion and Osmoregulation 2 to 1
Page 16 and 17: Epidermis Frontal gland Esophagus R
Page 18 and 19: Development Paleonemertea, Hoplonem
Page 20 and 21: Late-stage Cerebratulus sp. Pilidiu
Page 22 and 23: Nemertean Taxonomy Nemerteans are c
Page 24 and 25: Are Nemerteans sister taxa with fla

Phylum Nemertea (Rhynchocoela)

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